1. Field of the Invention
The present invention relates to the field of vehicle maintenance and repair. More specifically, the invention is directed to servicing transmission cooling systems.
2. Related Art
It is common for vehicles with automatic transmissions to have a cooling system for the transmission fluid in order to keep the operating temperature of the transmission within a desired range. Most cars, especially larger models, have such a transmission cooling system. Most trucks and vans require a larger transmission cooling system to handle extra stress placed on the transmission by, for example, carrying heavy loads or towing trailers. A typical transmission cooling system is connected to the transmission in such a way that transmission fluid is circulated from the transmission to a transmission fluid cooler through one line, then circulated through the transmission fluid cooler, and returned to the transmission through a second line.
A transmission cooling system can include, for example, a transmission fluid cooler inside the vehicle's radiator, so that the transmission fluid cooler is immersed in the engine coolant inside the radiator. Thus, engine coolant, typically a combination of water and antifreeze, flows over the outside of the transmission fluid cooler while transmission fluid flows on the inside of the transmission fluid cooler. Heat is transferred from the transmission fluid circulating inside the transmission fluid cooler to the engine coolant circulating outside the transmission fluid cooler. Air flow over the outside of the radiator cools the engine coolant. Other cooling devices may also be used, for example, a called a “heat exchanger” may be used in conjunction with or instead of the transmission fluid cooler described above. The transmission fluid cooler is also sometimes referred to as a transmission “oil cooler.” A common design among all these devices is that each circulates fluid from the transmission through the device, in order to cool the fluid, and then returns the cooled fluid to the transmission. Thus, in a transmission cooling system, transmission fluid is circulated from the vehicle's transmission system, through a transmission fluid cooler which controls the temperature of the transmission fluid, and returns to circulate through the transmission, thereby keeping the transmission within desired operating temperature range.
For various reasons such as extended use of the vehicle or transmission failure, the transmission fluid can become “dirty” or contaminated with debris, for example, metal flakes from worn parts inside the transmission. Such debris can accumulate inside the transmission cooling system, in particular, inside the transmission cooler causing it to “clog” or become incapable of sufficient circulation of transmission fluid to provide adequate cooling. Occasionally, a transmission cooler becomes so clogged that it must be replaced. Transmission cooling system clogging can also lead to premature transmission failure. It is, therefore, crucial to clean the transmission cooling system as part of normal periodic transmission servicing. In addition, when a transmission is removed to be rebuilt or replaced with a new or rebuilt transmission, the transmission cooling system is typically cleaned to avoid contamination of the reinstalled transmission.
A number of conventional means are available for cleaning transmission cooling systems. One conventional means uses a pressurized container containing a liquid cleaner, for example, a can containing compressed solvent. Use of such means has many disadvantages. For example, the amount of cleaning that can be performed is limited by the amount of solvent and the can pressure, which may require the use and expense of extra cans. In addition, the cleaning liquid is only used once, which is wasteful because cleaning liquid is typically not completely dirty after only one use and can be used again. Disposing cleaning liquid which is capable of being reused is not only wasteful, but is also harmful to the environment.
Another disadvantage of using a compressed solvent can is that it does not provide a measure of the effectiveness of the cleaning. As a result, a transmission fluid cooler, which appears to have been cleaned may still be incapable of sufficient circulation of transmission fluid to provide adequate cooling, but may be reused and cause transmission overheating and damage.
Other conventional methods of cleaning transmission cooling systems may use air pressure. A source of such air pressure may be a pressurized system of air hoses commonly found in auto repair shops, typically referred to as “shop air,” typically at a pressure of 100.0 to 120.0 pounds per square inch (“psi”). Use of such methods is disadvantageous in that shop air may not be available at the location where the vehicle is to be serviced. Further, high air pressure can present safety concerns for the operators. In addition, shop air methods suffer from other disadvantages, such as using the cleaning liquid only once, which is wasteful because cleaning liquid is typically not completely dirty after only one use and can be used again. As stated above, such wastefulness is also harmful to the environment.
Accordingly, there is an intense need in the art for a new cooler flusher method and apparatus that can overcome the disadvantages and drawbacks in the conventional art; that can improve cost, efficiency, and safety; and that can remove environmental concerns.